/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2009 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ /* * Copyright (c) 2018, Joyent, Inc. */ /* * amd64 specific setup routine - relocate ld.so's symbols, setup its * environment, map in loadable sections of the executable. * * Takes base address ld.so was loaded at, address of ld.so's dynamic * structure, address of process environment pointers, address of auxiliary * vector and * argv[0] (process name). * If errors occur, send process signal - otherwise * return executable's entry point to the bootstrap routine. */ #include #include #include #include #include #include #include #include "_rtld.h" #include "_audit.h" #include "msg.h" /* * Number of bytes to save for register usage. */ uint_t _plt_save_size; void (*_plt_fp_save)(void *); void (*_plt_fp_restore)(void *); extern void _elf_rtbndr_fp_save_orig(void *); extern void _elf_rtbndr_fp_restore_orig(void *); extern void _elf_rtbndr_fp_fxsave(void *); extern void _elf_rtbndr_fp_fxrestore(void *); extern void _elf_rtbndr_fp_xsave(void *); extern void _elf_rtbndr_fp_xrestore(void *); /* * Based on what the kernel has told us, go through and set up the various * pointers that we'll need for elf_rtbndr for the FPU. */ static void _setup_plt_fpu(int kind, size_t len) { /* * If we didn't get a length for some reason, fall back to the old * implementation. */ if (len == 0) kind = -1; switch (kind) { case AT_386_FPINFO_FXSAVE: _plt_fp_save = _elf_rtbndr_fp_fxsave; _plt_fp_restore = _elf_rtbndr_fp_fxrestore; _plt_save_size = len; break; /* * We can treat processors that don't correctly handle the exception * information in xsave the same way we do others. The information * that may or may not be properly saved and restored should not be * relevant to us because of the ABI. */ case AT_386_FPINFO_XSAVE: case AT_386_FPINFO_XSAVE_AMD: _plt_fp_save = _elf_rtbndr_fp_xsave; _plt_fp_restore = _elf_rtbndr_fp_xrestore; _plt_save_size = len; break; default: _plt_fp_save = _elf_rtbndr_fp_save_orig; _plt_fp_restore = _elf_rtbndr_fp_restore_orig; /* * The ABI says that 8 floating point registers are used for * passing arguments (%xmm0 through %xmm7). Because these * registers on some platforms may shadow the %ymm and %zmm * registers, we end up needing to size this for the maximally * sized register we care about, a 512-bit (64-byte) zmm * register. */ _plt_save_size = 64 * 8; break; } } /* VARARGS */ unsigned long _setup(Boot *ebp, Dyn *ld_dyn) { ulong_t reladdr, relacount, ld_base = 0; ulong_t relaent = 0, pltrelsz = 0; ulong_t strtab, soname, interp_base = 0; char *_rt_name, **_envp, **_argv; int _syspagsz = 0, fd = -1; uint_t _flags = 0; uint_t hwcap[2] = { 0, 0 }; Dyn *dyn_ptr; Phdr *phdr = NULL; Rt_map *lmp; auxv_t *auxv, *_auxv; uid_t uid = (uid_t)-1, euid = (uid_t)-1; gid_t gid = (gid_t)-1, egid = (gid_t)-1; char *_platform = NULL, *_execname = NULL, *_emulator = NULL; int auxflags = -1, fpkind = -1; size_t fpsize = 0; /* * Scan the bootstrap structure to pick up the basics. */ for (; ebp->eb_tag != EB_NULL; ebp++) switch (ebp->eb_tag) { case EB_LDSO_BASE: ld_base = (unsigned long)ebp->eb_un.eb_val; break; case EB_ARGV: _argv = (char **)ebp->eb_un.eb_ptr; break; case EB_ENVP: _envp = (char **)ebp->eb_un.eb_ptr; break; case EB_AUXV: _auxv = (auxv_t *)ebp->eb_un.eb_ptr; break; case EB_PAGESIZE: _syspagsz = (int)ebp->eb_un.eb_val; break; } /* * Search the aux. vector for the information passed by exec. */ for (auxv = _auxv; auxv->a_type != AT_NULL; auxv++) { switch (auxv->a_type) { case AT_EXECFD: /* this is the old exec that passes a file descriptor */ fd = (int)auxv->a_un.a_val; break; case AT_FLAGS: /* processor flags (MAU available, etc) */ _flags = auxv->a_un.a_val; break; case AT_PAGESZ: /* system page size */ _syspagsz = (int)auxv->a_un.a_val; break; case AT_PHDR: /* address of the segment table */ phdr = (Phdr *)auxv->a_un.a_ptr; break; case AT_BASE: /* interpreter base address */ if (ld_base == 0) ld_base = auxv->a_un.a_val; interp_base = auxv->a_un.a_val; break; case AT_SUN_UID: /* effective user id for the executable */ euid = (uid_t)auxv->a_un.a_val; break; case AT_SUN_RUID: /* real user id for the executable */ uid = (uid_t)auxv->a_un.a_val; break; case AT_SUN_GID: /* effective group id for the executable */ egid = (gid_t)auxv->a_un.a_val; break; case AT_SUN_RGID: /* real group id for the executable */ gid = (gid_t)auxv->a_un.a_val; break; case AT_SUN_PLATFORM: /* platform name */ _platform = auxv->a_un.a_ptr; break; case AT_SUN_EXECNAME: /* full pathname of execed object */ _execname = auxv->a_un.a_ptr; break; case AT_SUN_AUXFLAGS: /* auxiliary flags */ auxflags = (int)auxv->a_un.a_val; break; case AT_SUN_HWCAP: /* hardware capabilities */ hwcap[0] = (uint_t)auxv->a_un.a_val; break; case AT_SUN_HWCAP2: /* hardware capabilities */ hwcap[1] = (uint_t)auxv->a_un.a_val; break; case AT_SUN_EMULATOR: /* name of emulation library, if any */ _emulator = auxv->a_un.a_ptr; break; case AT_SUN_FPTYPE: fpkind = (int)auxv->a_un.a_val; break; case AT_SUN_FPSIZE: fpsize = (size_t)auxv->a_un.a_val; break; } } /* * Get needed info from ld.so's dynamic structure. */ /* LINTED */ dyn_ptr = (Dyn *)((char *)ld_dyn + ld_base); for (ld_dyn = dyn_ptr; ld_dyn->d_tag != DT_NULL; ld_dyn++) { switch (ld_dyn->d_tag) { case DT_RELA: reladdr = ld_dyn->d_un.d_ptr + ld_base; break; case DT_RELACOUNT: relacount = ld_dyn->d_un.d_val; break; case DT_RELAENT: relaent = ld_dyn->d_un.d_val; break; case DT_PLTRELSZ: pltrelsz = ld_dyn->d_un.d_val; break; case DT_STRTAB: strtab = ld_dyn->d_un.d_ptr + ld_base; break; case DT_SONAME: soname = ld_dyn->d_un.d_val; break; } } _rt_name = (char *)strtab + soname; /* * If we don't have a RELAENT, just assume the size. */ if (relaent == 0) relaent = sizeof (Rela); /* * As all global symbol references within ld.so.1 are protected * (symbolic), only RELATIVE and JMPSLOT relocations should be left * to process at runtime. Process all relocations now. */ relacount += (pltrelsz / relaent); for (; relacount; relacount--) { ulong_t roffset; roffset = ((Rela *)reladdr)->r_offset + ld_base; *((ulong_t *)roffset) += ld_base + ((Rela *)reladdr)->r_addend; reladdr += relaent; } /* * If an emulation library is being used, use that as the linker's * effective executable name. The real executable is not linked by this * linker. */ if (_emulator != NULL) { _execname = _emulator; rtld_flags2 |= RT_FL2_BRANDED; } /* * Initialize the dyn_plt_ent_size field. It currently contains the * size of the dyn_plt_template. It still needs to be aligned and have * space for the 'dyn_data' area added. */ dyn_plt_ent_size = ROUND(dyn_plt_ent_size, M_WORD_ALIGN) + sizeof (uintptr_t) + sizeof (uintptr_t) + sizeof (ulong_t) + sizeof (ulong_t) + sizeof (Sym); /* * Initialize the amd64 specific PLT relocation constants based on the * FP information that we have. */ _setup_plt_fpu(fpkind, fpsize); /* * Continue with generic startup processing. */ if ((lmp = setup((char **)_envp, (auxv_t *)_auxv, _flags, _platform, _syspagsz, _rt_name, ld_base, interp_base, fd, phdr, _execname, _argv, uid, euid, gid, egid, NULL, auxflags, hwcap)) == NULL) { rtldexit(&lml_main, 1); } return (LM_ENTRY_PT(lmp)()); }